Recombinant Human CTLA-4 Protein

Product Discontinued

Recombinant Human CTLA-4 Protein Summary

• Description: A recombinant protein with a C-Terminal hIgG-His-tag and corresponding to the amino acids 36-161 of Human CTLA-4
  
  

  Source:Baculovirus

  Amino Acid Sequence: ADLKAMHVAQ PAVVLASSRG IASFVCEYAS PGKATEVRVT VLRQADSQVT EVCAATYMMG NELTFLDDSI CTGTSSGNQV NLTIQGLRAM DTGLYICKVE LMYPPPYYLG IGNGTQIYVI DPEPCPDSDL EPKSCDKTHT CPPCPAPELL GGPSVFLFPP KPKDTLMISR TPEVTCVVVD VSHEDPEVKF NWYVDGVEVH NAKTKPREEQ YNSTYRVVSV LTVLHQDWLN GKEYKCKVSN KALPAPIEKT ISKAKGQPRE PQVYTLPPSR DELTKNQVSL TCLVKGFYPS DIAVEWESNG QPENNYKTTP PVLDSDGSFF LYSKLTVDKS RWQQGNVFSC SVMHEALHNH YTQKSLSLSP GKHHHHHH

• Source: Baculovirus
• Protein/Peptide Type: Recombinant Protein
• Gene: CTLA4
• Purity: >95%, by SDS-PAGE
• Endotoxin Note: < 1.0 EU per 1 microgram of protein (determined by LAL method)

Applications/Dilutions

• Dilutions:
  • SDS-Page
• Theoretical MW: 40.8 kDa.
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.

Packaging, Storage & Formulations

• Storage: Store at 4C short term. Aliquot and store at -20C long term. Avoid freeze-thaw cycles.
• Buffer: PBS (pH 7.4), 10% glycerol
• Preservative: No Preservative
• Concentration: 0.5 mg/ml
• Purity: >95%, by SDS-PAGE

Alternate Names for Recombinant Human CTLA-4 Protein

• CD
• CD152 antigen
• CD152
• CD152IDDM12
• CD28
• celiac disease 3
• CELIAC3
• CTLA4
• CTLA-4
• cytotoxic T-lymphocyte antigen 4
• cytotoxic T-lymphocyte protein 4
• Cytotoxic T-lymphocyte-associated antigen 4
• cytotoxic T-lymphocyte-associated protein 4
• cytotoxic T-lymphocyte-associated serine esterase-4
• GRD4
• GSE
• ICOS
• ligand and transmembrane spliced cytotoxic T lymphocyte associated antigen 4

Background

Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4), also known as CD152, is a cell surface glycoprotein belonging to the immunoglobulin family with a role in regulation of T cell activation (1). Human CTLA-4 is a 223 amino acid (aa) protein with a theoretical molecular weight of 24.6 kDa containing a leader peptide, a IgV-like domain, a transmembrane domain, and a cytoplasmic tail (1,2). CTLA-4 is both structurally and functionally related with another member of the immunoglobulin-related receptor family, CD28 (1-3). CTLA-4 and CD28 receptors are both expressed by CD4+ and CD8+ T cells and share two common ligands, CD80 (B7.1) and CD86 (B7.2), expressed on the surface of antigen presenting cells (APCs) (2,3). While CD28 is present on the plasma membrane of T cells, CTLA-4 is predominantly expressed intracellularly on vesicles in FoxP3+ regulatory T (Treg) cells and activated T cells due to endocytosis (3). While they share ligands, the two receptors have opposing functions in T cell activation; CD28 is involved in activation of T cells, while CTLA-4 functions as a negative regulator of T cell response (2,3). One of the primary functions of CTLA-4 is preventing autoimmunity (1-4).

Similar to programmed cell death protein 1 (PD-1), CTLA-4 is an inhibitory immune checkpoint protein (3,5). Checkpoint blockade immunotherapy using drugs or antibodies to target CTLA-4 is one of the main approaches for cancer treatment (5). A number of drugs targeting CTLA-4, or a combination of CTLA-4/PD-1, have been approved for treatment of various cancers like melanoma, renal cell carcinoma, and colorectal cancer (5). While blocking CTLA-4 in the tumor microenvironment is a promising cancer therapeutic, the absence of CTLA-4 under normal conditions can have deleterious effects. Studies have found that patients with CTLA-4 deficiency or mutations have clinical features associated with autoimmunity and immune dysregulation (4). Treatment options for CTLA-4 deficiency includes immunoglobulin-replacement therapy, corticosteroids, CTLA-4-immunoglobulin (Ig) fusion protein, and, in life-threatening cases, hematopoietic stem cell transplantation (4,6). Additionally, engaging CD80/CD86 with CTLA-4-Ig is a common immunosuppressive treatment for rheumatoid arthritis and kidney transplant recipients (6).

References

1. Romo-Tena, J., Gomez-Martin, D., & Alcocer-Varela, J. (2013). CTLA-4 and autoimmunity: new insights into the dual regulator of tolerance. Autoimmunity reviews, 12(12), 1171-1176. https://doi.org/10.1016/j.autrev.2013.07.002

2. Hosseini, A., Gharibi, T., Marofi, F., Babaloo, Z., & Baradaran, B. (2020). CTLA-4: From mechanism to autoimmune therapy. International immunopharmacology, 80, 106221. https://doi.org/10.1016/j.intimp.2020.106221

3. Rowshanravan, B., Halliday, N., & Sansom, D. M. (2018). CTLA-4: a moving target in immunotherapy. Blood, 131(1), 58-67. https://doi.org/10.1182/blood-2017-06-741033

4. Verma, N., Burns, S. O., Walker, L., & Sansom, D. M. (2017). Immune deficiency and autoimmunity in patients with CTLA-4 (CD152) mutations. Clinical and experimental immunology, 190(1), 1-7. https://doi.org/10.1111/cei.12997

5. Rotte A. (2019). Combination of CTLA-4 and PD-1 blockers for treatment of cancer. Journal of experimental & clinical cancer research : CR, 38(1), 255. https://doi.org/10.1186/s13046-019-1259-z

6. Bluestone, J. A., St Clair, E. W., & Turka, L. A. (2006). CTLA4Ig: bridging the basic immunology with clinical application. Immunity, 24(3), 233-238. https://doi.org/10.1016/j.immuni.2006.03.001

Limitations

This product is for research use only and is not approved for use in humans or in clinical diagnosis. Peptides and proteins are guaranteed for 3 months from date of receipt.

Bioinformatics

• Gene Symbol: CTLA4